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1.
Brain ; 146(9): 3634-3647, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36995941

RESUMO

Cerebral cavernous malformations (CCMs) and spinal cord cavernous malformations (SCCMs) are common vascular abnormalities of the CNS that can lead to seizure, haemorrhage and other neurological deficits. Approximately 85% of patients present with sporadic (versus congenital) CCMs. Somatic mutations in MAP3K3 and PIK3CA were recently reported in patients with sporadic CCM, yet it remains unknown whether MAP3K3 mutation is sufficient to induce CCMs. Here we analysed whole-exome sequencing data for patients with CCM and found that ∼40% of them have a single, specific MAP3K3 mutation [c.1323C>G (p.Ile441Met)] but not any other known mutations in CCM-related genes. We developed a mouse model of CCM with MAP3K3I441M uniquely expressed in the endothelium of the CNS. We detected pathological phenotypes similar to those found in patients with MAP3K3I441M. The combination of in vivo imaging and genetic labelling revealed that CCMs were initiated with endothelial expansion followed by disruption of the blood-brain barrier. Experiments with our MAP3K3I441M mouse model demonstrated that CCM can be alleviated by treatment with rapamycin, the mTOR inhibitor. CCM pathogenesis has usually been attributed to acquisition of two or three distinct genetic mutations involving the genes CCM1/2/3 and/or PIK3CA. However, our results demonstrate that a single genetic hit is sufficient to cause CCMs.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central , Proteínas Proto-Oncogênicas , Animais , Camundongos , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Mutação/genética , Fenótipo , Medula Espinal/patologia
2.
Int Ophthalmol ; 44(1): 142, 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38493427

RESUMO

PURPOSE: The purpose of this study was to investigate the effect of circ_HLCS on age-related cataract (ARC). METHODS: Circ_HLCS, microRNA (miR)-338-3p, and bisphosphate 3'-nucleotidase 1 (BPNT1) were quantified by quantitative real-time polymerase chain reaction or western blot. Cell proliferation and cell viability were assessed by the 5-Ethynyl-2'-deoxyuridinr and cell counting kit-8 assays. Cell apoptosis was detected by flow cytometry. Targeted correlations among circ_HLCS, miR-338-3p, and BPNT1 were verified by the dual-luciferase reporter and RNA pull-down assays. RESULTS: circ_HLCS was diminished in ARC tissues and UV-treated SRA01/04 cells. Elevated content of circ_HLCS undermined UV-induced cell proliferation inhibition and apoptosis. Mechanistically, circ_HLCS directly targeted miR-338-3p, and circ_HLCS regulated BPNT1 expression through miR-338-3p. Furthermore, reduction of miR-338-3p ameliorated UV-induced SRA01/04 cell damage by increasing BPNT1 expression. CONCLUSION: Taken together, these data suggested that circ_HLCS inhibited apoptosis of UV-treated SRA01/04 cells by miR-338-3p/BPNT1 axis. Therefore, circ_HLCS might be a potential therapeutic target for ARC.


Assuntos
Cristalino , MicroRNAs , Humanos , RNA Circular/genética , Apoptose , Proliferação de Células , Células Epiteliais , MicroRNAs/genética
3.
Anal Chem ; 95(30): 11326-11334, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37409763

RESUMO

Single-cell omics is critical in revealing population heterogeneity, discovering unique features of individual cells, and identifying minority subpopulations of interest. As one of the major post-translational modifications, protein N-glycosylation plays crucial roles in various important biological processes. Elucidation of the variation in N-glycosylation patterns at single-cell resolution may largely facilitate the understanding of their key roles in the tumor microenvironment and immune therapy. However, comprehensive N-glycoproteome profiling for single cells has not been achieved due to the extremely limited sample amount and incompatibility with the available enrichment strategies. Here, we have developed an isobaric labeling-based carrier strategy for highly sensitive intact N-glycopeptide profiling for single cells or a small number of rare cells without enrichment. Isobaric labeling has unique multiplexing properties, by which the "total" signal from all channels triggers MS/MS fragmentation for N-glycopeptide identification, while the reporter ions provide quantitative information. In our strategy, a carrier channel using N-glycopeptides obtained from bulk-cell samples significantly improved the "total" signal of N-glycopeptides and, therefore, promoted the first quantitative analysis of averagely 260 N-glycopeptides from single HeLa cells. We further applied this strategy to study the regional heterogeneity of N-glycosylation of microglia in mouse brain and discovered region-specific N-glycoproteome patterns and cell subtypes. In conclusion, the glycocarrier strategy provides an attractive solution for sensitive and quantitative N-glycopeptide profiling of single/rare cells that cannot be enriched by traditional workflows.


Assuntos
Glicopeptídeos , Espectrometria de Massas em Tandem , Humanos , Animais , Camundongos , Glicopeptídeos/análise , Células HeLa , Glicosilação , Processamento de Proteína Pós-Traducional , Proteoma/análise
4.
J Transl Med ; 21(1): 897, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072965

RESUMO

BACKGROUND: The alkaloid camptothecin analog SN38 is a potent antineoplastic agent, but cannot be used directly for clinical application due to its poor water solubility. Currently, the prodrug approach on SN38 has resulted in 3 FDA-approved cancer therapeutics, irinotecan, ONIVYDE, and Trodelvy. However, only 2-8% of irinotecan can be transformed enzymatically in vivo into the active metabolite SN38, which severely limits the drug's efficacy. While numerous drug delivery systems have been attempted to achieve effective SN38 delivery, none have produced drug products with antitumor efficacy better than irinotecan in clinical trials. Therefore, novel approaches are urgently needed for effectively delivering SN38 to cancer cells with better efficacy and lower toxicity. METHODS: Based on the unique properties of human serum albumin (HSA), we have developed a novel single protein encapsulation (SPE) technology to formulate cancer therapeutics for improving their pharmacokinetics (PK) and antitumor efficacy and reducing their side effects. Previous application of SPE technology to doxorubicin (DOX) formulation has led to a promising drug candidate SPEDOX-6 (FDA IND #, 152154), which will undergo a human phase I clinical trial. Using the same SPE platform on SN38, we have now produced two SPESN38 complexes, SPESN38-5 and SPESN38-8. We conducted their pharmacological evaluations with respect to maximum tolerated dose, PK, and in vivo efficacy against colorectal cancer (CRC) and soft tissue sarcoma (STS) in mouse models. RESULTS: The lyophilized SPESN38 complexes can dissolve in aqueous media to form clear and stable solutions. Maximum tolerated dose (MTD) of SPESN38-5 is 250 mg/kg by oral route (PO) and 55 mg/kg by intravenous route (IV) in CD-1 mice. SPESN38-8 has the MTD of 45 mg/kg by IV in the same mouse model. PK of SPESN38-5 by PO at 250 mg/kg gave mouse plasma AUC0-∞ of 0.05 and 4.5 nmol × h/mL for SN38 and SN38 glucuronidate (SN38G), respectively, with a surprisingly high molar ratio of SN38G:SN38 = 90:1. However, PK of SPESN38-5 by IV at 55 mg/kg yielded much higher mouse plasma AUC0-∞ of 19 and 28 nmol × h/mL for SN38 and SN38G, producing a much lower molar ratio of SN38G:SN38 = 1.5:1. Antitumor efficacy of SPESN38-5 and irinotecan (control) was evaluated against HCT-116 CRC xenograft tumors. The data indicates that SPESN38-5 by IV at 55 mg/kg is more effective in suppressing HCT-116 tumor growth with lower systemic toxicity compared to irinotecan at 50 mg/kg. Additionally, SPESN38-8 and DOX (control) by IV were evaluated in the SK-LMS-1 STS mouse model. The results show that SPESN38-8 at 33 mg/kg is highly effective for inhibiting SK-LMS-1 tumor growth with low toxicity, in contrast to DOX's insensitivity to SK-LMS-1 with high toxicity. CONCLUSION: SPESN38 complexes provide a water soluble SN38 formulation. SPESN38-5 and SPESN38-8 demonstrate better PK values, lower toxicity, and superior antitumor efficacy in mouse models, compared with irinotecan and DOX.


Assuntos
Antineoplásicos Fitogênicos , Antineoplásicos , Neoplasias Colorretais , Humanos , Camundongos , Animais , Irinotecano/uso terapêutico , Irinotecano/farmacocinética , Ensaios Antitumorais Modelo de Xenoenxerto , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Modelos Animais de Doenças , Água , Linhagem Celular Tumoral , Antineoplásicos Fitogênicos/farmacocinética
5.
Nature ; 549(7670): 43-47, 2017 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-28825707

RESUMO

Quantum key distribution (QKD) uses individual light quanta in quantum superposition states to guarantee unconditional communication security between distant parties. However, the distance over which QKD is achievable has been limited to a few hundred kilometres, owing to the channel loss that occurs when using optical fibres or terrestrial free space that exponentially reduces the photon transmission rate. Satellite-based QKD has the potential to help to establish a global-scale quantum network, owing to the negligible photon loss and decoherence experienced in empty space. Here we report the development and launch of a low-Earth-orbit satellite for implementing decoy-state QKD-a form of QKD that uses weak coherent pulses at high channel loss and is secure because photon-number-splitting eavesdropping can be detected. We achieve a kilohertz key rate from the satellite to the ground over a distance of up to 1,200 kilometres. This key rate is around 20 orders of magnitudes greater than that expected using an optical fibre of the same length. The establishment of a reliable and efficient space-to-ground link for quantum-state transmission paves the way to global-scale quantum networks.

6.
Int Ophthalmol ; 43(5): 1687-1699, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36372820

RESUMO

PURPOSE: ß-asarone is the prime component of essential oil extracted from Acori graminei Rhizoma, which plays an inhibitory role in various tumors. Here, we aim to investigate the functions as well as the mechanism of ß-asarone in retinoblastoma (RB). METHODS: RB cell lines SO-Rb50 and HXO-Rb44 were treated with different doses of ß-asarone. Then, CCK8 and BrdU experiments were adopted to examine the RB cell proliferation. Wound healing test and Transwell assay were employed to detect cell migration and invasion. RB cell apoptosis was tested by flow cytometry and Western blot. An RB cell xenograft model was constructed on nude mice for testing the role of ß-asarone on RB cell growth in vivo. RT-PCR and Western blot were used to determine the effect of ß-asarone on Wnt/ß-catenin signaling pathway. Furthermore, the Wnt/ß-catenin pathway inhibitor PNU-74654 and activator HLY78 were administered to RB cells for confirming the effects of ß-asarone in Wnt/ß-catenin pathway. RESULTS: In vivo experiment showed that ß-asarone attenuated SO-Rb50 cell growth in nude mice. Further research found that ß-asarone significantly repressed Wnt/ß-catenin canonical pathway activation. CONCLUSION: Prior inhibition of Wnt/ß-catenin pathway abolished the antitumor effects induced by ß-asarone. ß-asarone exerted antitumor effects in RB cells by inactivating the Wnt/ß-catenin signaling pathway.


Assuntos
Neoplasias da Retina , Retinoblastoma , Animais , Camundongos , Humanos , Retinoblastoma/tratamento farmacológico , Retinoblastoma/patologia , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Camundongos Nus , Linhagem Celular Tumoral , Apoptose , Neoplasias da Retina/tratamento farmacológico , Proliferação de Células/fisiologia
7.
Int J Mol Sci ; 23(11)2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35682885

RESUMO

Molecular glue (MG) compounds are a type of unique small molecule that can change the protein-protein interactions (PPIs) and interactomes by degrading, stabilizing, or activating the target protein after their binging. These small-molecule MGs are gradually being recognized for their potential application in treating human diseases, including cancer. Evidence suggests that small-molecule MG compounds could essentially target any proteins, which play critical roles in human disease etiology, where many of these protein targets were previously considered undruggable. Intriguingly, most MG compounds with high efficacy for cancer treatment can glue on and control multiple key protein targets. On the other hand, a single key protein target can also be glued by multiple MG compounds with distinct chemical structures. The high flexibility of MG-protein interaction profiles provides rich soil for the growth and development of small-molecule MG compounds that can be used as molecular tools to assist in unraveling disease mechanisms, and they can also facilitate drug development for the treatment of human disease, especially human cancer. In this review, we elucidate this concept by using various types of small-molecule MG compounds and their corresponding protein targets that have been documented in the literature.


Assuntos
Neoplasias , Doenças Neurodegenerativas , Humanos , Neoplasias/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Ligação Proteica , Proteínas/metabolismo , Proteólise , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/uso terapêutico , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
8.
Molecules ; 27(12)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35744795

RESUMO

Irinotecan and Topotecan are two Camptothecin derivatives (CPTs) whose resistance is associated with the high expression of breast cancer resistance protein (BCRP) and P-glycoprotein (P-gp). To reverse this resistance, two novel CPTs, FL77-28 (7-(3-Fluoro-4-methylphenyl)-10,11-methylenedioxy-20(S)-CPT) and FL77-29 (7-(4-Fluoro-3-methylphenyl)-10,11-methylenedioxy-20(S)-CPT), were synthesized by our group. In this study, the anti-tumor activities of FL77-28, FL77-29, and their parent, FL118 (10,11-methylenedioxy-20(S)-CPT), were evaluated and the results showed that FL77-28 and FL77-29 had stronger anti-tumor activities than FL118. The transport and uptake of FL118, FL77-28, and FL77-29 were investigated in Caco-2 cells for the preliminary prediction of intestinal absorption. The apparent permeability coefficient from apical to basolateral (Papp AP-BL) values of FL77-28 and FL77-29 were (2.32 ± 0.04) × 10-6 cm/s and (2.48 ± 0.18) × 10-6 cm/s, respectively, suggesting that the compounds had moderate absorption. Since the transport property of FL77-28 was passive diffusion and the efflux ratio (ER) was less than 2, two chemical inhibitors were added to further confirm the involvement of efflux proteins. The results showed that FL77-28 was not a substrate of P-gp or BCRP, but FL77-29 was mediated by P-gp. In conclusion, FL77-28 might be a promising candidate to overcome drug resistance induced by multiple efflux proteins.


Assuntos
Camptotecina , Proteínas de Neoplasias , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transporte Biológico , Células CACO-2 , Camptotecina/análogos & derivados , Camptotecina/metabolismo , Humanos , Proteínas de Neoplasias/metabolismo
9.
Anal Chem ; 93(11): 4884-4893, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33687211

RESUMO

Quantitative proteomics in large cohorts is highly valuable for clinical/pharmaceutical investigations but often suffers from severely compromised reliability, accuracy, and reproducibility. Here, we describe an ultra-high-resolution IonStar method achieving reproducible protein measurement in large cohorts while minimizing the ratio compression problem, by taking advantage of the exceptional selectivity of ultra-high-resolution (UHR)-MS1 detection (240k_FWHM@m/z = 200). Using mixed-proteome benchmark sets reflecting large-cohort analysis with technical or biological replicates (N = 56), we comprehensively compared the quantitative performances of UHR-IonStar vs a state-of-the-art SWATH-MS method, each with their own optimal analytical platforms. We confirmed a cutting-edge micro-liquid chromatography (LC)/Triple-TOF with Spectronaut outperforms nano-LC/Orbitrap for SWATH-MS, which was then meticulously developed/optimized to maximize sensitivity, reproducibility, and proteome coverage. While the two methods with distinct principles (i.e., MS1- vs MS2-based) showed similar depth-of-analysis (∼6700-7000 missing-data-free proteins quantified, 1% protein-false discovery rate (FDR) for entire set, 2 unique peptides/protein) and good accuracy/precision in quantifying high-abundance proteins, UHR-IonStar achieved substantially superior quantitative accuracy, precision, and reproducibility for lower-abundance proteins (a category that includes most regulatory proteins), as well as much-improved sensitivity/selectivity for discovering significantly altered proteins. Furthermore, compared to SWATH-MS, UHR-IonStar showed markedly higher accuracy for a single analysis of each sample across a large set, which is an inadequately investigated albeit critical parameter for large-cohort analysis. Finally, we compared UHR-IonStar vs SWATH-MS in measuring the time courses of altered proteins in paclitaxel-treated cells (N = 36), where dysregulated biological pathways have been very well established. UHR-IonStar discovered substantially more well-recognized biological processes/pathways induced by paclitaxel. Additionally, UHR-IonStar showed markedly superior ability than SWATH-MS in accurately depicting the time courses of well known to be paclitaxel-induced biomarkers. In summary, UHR-IonStar represents a reliable, robust, and cost-effective solution for large-cohort proteomic quantification with excellent accuracy and precision.


Assuntos
Proteômica , Espectrometria de Massas em Tandem , Estudos de Coortes , Proteoma , Reprodutibilidade dos Testes
10.
Chem Pharm Bull (Tokyo) ; 69(11): 1054-1060, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34719586

RESUMO

In the evaluation of the druggability of candidate compounds, it was vital to predict the oral bioavailability of compounds from apparent permeability (Papp) across Caco-2 cell-culture model of intestinal epithelium cultured on commercial transwell plate inserts. The study was to investigate the transport characteristics and permeability of FL118 (10, 11-Methylenedioxy-20(S)-camptothecin) derivatives 7-Q6 (7-(4-Ethylphenyl)-10, 11-methylenedioxy-20(S)-camptothecin) and 7-Q20 (7-(4-Trifluoromethylphenyl)-10, 11-methylenedioxy-20(S)-camptothecin). Transport characteristics and permeability of the tested compounds to the small intestine were assessed at different concentrations (0.5, 1 µM) via Caco-2 cell monolayers model in vitro. Uptake studies based on Caco-2 cells, including temperatures, concentrations, and the influence of efflux transporters, were combined to confirm the transport characteristics of the tested compounds. Furthermore, cytotoxicity results showed that the concentrations used in the experiments were non-toxic and harmless to cells. In addition, The Papp of 7-Q6 was (3.69 ± 1.07) × 10-6 cm/s with efflux ratio (ER) 0.98, while the Papp of 7-Q20 was (7.78 ± 0.89) × 10-6 cm/s with ER 1.05 for apical-to-basolateral (AP→BL) at 0.5 µM, suggesting that 7-Q20 might possess higher oral bioavailability in vivo. Furthermore, P-glycoprotein (P-gp) was proved to slightly affect the accumulations of 7-Q20, while the absorption of 7-Q6 was irrelevant with P-gp and breast cancer resistant protein (BCRP) based on the cellular uptake assays. Accordingly, 7-Q6 was completely absorbed by passive diffusion, and 7-Q20 was mainly dependent on passive diffusion with being effluxed by P-gp slightly. Meanwhile, both 7-Q6 and 7-Q20 were potential antitumor drugs that might exhibit high oral bioavailability in the body.


Assuntos
Antineoplásicos/química , Benzodioxóis/química , Membrana Celular/metabolismo , Indolizinas/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/administração & dosagem , Benzodioxóis/administração & dosagem , Disponibilidade Biológica , Transporte Biológico , Células CACO-2 , Camptotecina/química , Camptotecina/metabolismo , Membrana Celular/ultraestrutura , Permeabilidade da Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Absorção Gastrointestinal , Humanos , Indolizinas/administração & dosagem , Mucosa Intestinal/metabolismo
11.
Opt Express ; 28(1): 369-378, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118965

RESUMO

High-fidelity transmission of polarization encoded qubits plays a key role in long distance quantum communication. By establishing the channel between ground and satellite, the communication distance can even exceed thousands of kilometers. Aimed to achieve the efficient uplink quantum communication, here we describe a high-fidelity polarization design of a transmitting antenna with an average polarization extinction ratio of 887:1 by a local test. We also implement a feasible polarization-compensation scheme for satellite motions with a fidelity exceeding 0.995 ± 0.001. Based on these works, we demonstrate the ground-to-satellite entanglment distribution with a violation of Bell inequality by 2.312±0.096, which is well above the classic limit 2.

12.
Neurochem Res ; 45(2): 455-464, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31853718

RESUMO

Astrocytes respond to all forms of central nervous system (CNS) insults by a process referred to as reactive astrogliosis. Inhibition of astrocyte growth and activation is an important strategy for promoting injured CNS repair. STAT3 (signal transducer and activator of transcription 3) is reported to be a critical regulator of astrogliosis, and resveratrol (RES, a dietary polyphenol) is considered to be a natural inhibitor of STAT3 expression and phosphorylation. In this study, we investigated the effects of RES on STAT3 expression and phosphorylation, and then on the proliferation and activation of astrocytes, a critical process in reactive astrogliosis, in rat primary cultured astrocytes and an in vitro scratch-wound model. RES downregulated the expression levels of STAT3, P-STAT3 and GFAP (glial fibrillary acidic protein) in cultured astrocytes. The positive index of Ki67 was apparently reduced in cultured astrocytes after RES treatment. Meanwhile, cultured astrocyte proliferation and activation were attenuated by RES. Moreover, in the established in vitro scratch-wound model the increased expression levels of STAT3, P-STAT3 and GFAP induced by scratching injury were also clearly inhibited by RES. In addition, the inhibitory effect of RES on cell proliferation was similar to that of AG490 (a selective inhibitor of STAT3 phosphorylation) and abrogated by Colivelin (a STAT3 activator) stimuli. Taken together, our data suggest that RES is able to inhibit reactive astrocyte proliferation and activation mainly via deactivating STAT3 pathway. So RES may have a therapeutic benefit for the treatment of the injured CNS.


Assuntos
Astrócitos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Resveratrol/farmacologia , Fator de Transcrição STAT3/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Antígeno Ki-67/metabolismo , Ratos , Fator de Transcrição STAT3/agonistas , Fator de Transcrição STAT3/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Tirfostinas/farmacologia
13.
Cell Mol Biol (Noisy-le-grand) ; 66(6): 71-75, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33040788

RESUMO

In this study, we investigated the effect of latanoprost on the expression of TGF- ß1 and Wnt / ß - Catenin signal pathway in the choroid of form-deprivation myopia model rats. Forty rats were randomly divided into two groups: the control group and the FDM model group. Each group had 20 rats. The FDM model group was established by feeding latanoprost daily for 28 days. 15 rats in each group were used to measure the length of the ocular axis and the level of TGF-ß1 in choroidal tissue; the remaining 5 rats in each group were used for choroidal fibroblast culture. After modeling, the rats were killed, the length of the ocular axis was measured with a vernier caliper, and the level of TGF - ß1 protein and mRNA in the choroidal tissue of each group were measured with RT-PCR method. Results showed that compared with the control group, there was a significant difference in the axial length of the FDM model group (P< 0.05). There was a significant difference in the expression of TGF- ß1 protein and mRNA between the two groups (P<0.05). The cultured cells were identified as choroidal fibroblasts by immunocytochemistry. There was no significant difference (P>0.05) in the comparison of GSK3 ß protein in choroidal fibroblasts of rats in each group. TGF-ß 1 and APC protein in FDM group were significantly lower than those in the control group (P<0.05), while dcl3, p21-gsk3 ß and ß - Catenin proteins were significantly higher (P<0.05), and there was no significant difference (P>0.05) in the ratio of various indexes protein in FDM + ddk1 group and the comparison of TGF - ß1 and APC protein in FDM + ddk1 group and FDM group The expression of dcl3, p21-gsk3 ß and ß - Catenin decreased significantly (P<0.05). There was no significant difference in the expression of GSK3 ß mRNA in the choroidal fibroblasts of each group (P>0.05). The expression of TGF - ß 1 and APC mRNA in FDM group was significantly lower than that in the control group (P<0.05), while the expression of dcl3, p21-gsk3 ß and ß-catenin mRNA in FDM + ddk1 group was significantly higher than that in the control group (P<0.05) >In FDM + ddk1 group, TGF-ß 1 and APC mRNA were significantly lower than those in FDM group (P<0.05), while dcl3, p21-gsk3 ß and ß-Catenin mRNA were significantly higher (P<0.05).


Assuntos
Corioide/efeitos dos fármacos , Latanoprosta/farmacologia , Miopia/tratamento farmacológico , Fator de Crescimento Transformador beta1/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Animais , Células Cultivadas , Corioide/metabolismo , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Masculino , Miopia/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Opt Express ; 26(15): 18897-18905, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30114149

RESUMO

Free-space quantum key distribution (QKD) is important to realize a global-scale quantum communication network. However, performing QKD in daylight against the strong background light noise is a major challenge. Here, we develop the stochastic parallel gradient descent (SPGD) algorithm with a deformable mirror to improve the signal-to-noise ratio (SNR). We then experimentally demonstrate free-space QKD in the presence of urban daylight. The final secure key rate of the QKD is 98∼419 bps throughout the majority of the daylight hours.

15.
Phys Rev Lett ; 120(3): 030501, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29400544

RESUMO

We perform decoy-state quantum key distribution between a low-Earth-orbit satellite and multiple ground stations located in Xinglong, Nanshan, and Graz, which establish satellite-to-ground secure keys with ∼kHz rate per passage of the satellite Micius over a ground station. The satellite thus establishes a secure key between itself and, say, Xinglong, and another key between itself and, say, Graz. Then, upon request from the ground command, Micius acts as a trusted relay. It performs bitwise exclusive or operations between the two keys and relays the result to one of the ground stations. That way, a secret key is created between China and Europe at locations separated by 7600 km on Earth. These keys are then used for intercontinental quantum-secured communication. This was, on the one hand, the transmission of images in a one-time pad configuration from China to Austria as well as from Austria to China. Also, a video conference was performed between the Austrian Academy of Sciences and the Chinese Academy of Sciences, which also included a 280 km optical ground connection between Xinglong and Beijing. Our work clearly confirms the Micius satellite as a robust platform for quantum key distribution with different ground stations on Earth, and points towards an efficient solution for an ultralong-distance global quantum network.

16.
Proc Natl Acad Sci U S A ; 112(34): 10697-702, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26261306

RESUMO

The evolutionarily conserved Elongator complex, which is composed of six subunits elongator protein 1 (Elp1 to -6), plays vital roles in gene regulation. The molecular hallmark of familial dysautonomia (FD) is the splicing mutation of Elp1 [also known as IκB kinase complex-associated protein (IKAP)] in the nervous system that is believed to be the primary cause of the devastating symptoms of this disease. Here, we demonstrate that disease-related mutations in Elp1 affect Elongator assembly, and we have determined the structure of the C-terminal portion of human Elp1 (Elp1-CT), which is sufficient for full-length Elp1 dimerization, as well as the structure of the cognate dimerization domain of yeast Elp1 (yElp1-DD). Our study reveals that the formation of the Elp1 dimer contributes to its stability in vitro and in vivo and is required for the assembly of both the human and yeast Elongator complexes. Functional studies suggest that Elp1 dimerization is essential for yeast viability. Collectively, our results identify the evolutionarily conserved dimerization domain of Elp1 and suggest that the pathological mechanisms underlying the onset and progression of Elp1 mutation-related disease may result from impaired Elongator activities.


Assuntos
Proteínas de Transporte/química , Splicing de RNA/genética , Animais , Proteínas de Transporte/genética , Sequência Conservada , Dimerização , Progressão da Doença , Disautonomia Familiar/genética , Disautonomia Familiar/fisiopatologia , Histona Acetiltransferases/química , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Complexos Multiproteicos , Fatores de Alongamento de Peptídeos/química , Fenótipo , Conformação Proteica , Mapeamento de Interação de Proteínas , Estabilidade Proteica , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Relação Estrutura-Atividade , Fatores de Elongação da Transcrição
17.
Opt Express ; 25(10): 10716-10723, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28788761

RESUMO

We report a 17-km free-space quantum key distribution (QKD) experiment using an engineering model of the space-bound optical transmitter and a ground station for satellite-ground QKD. The final key rate of ~ 0.5 kbps is achieved in this experiment with the quantum bit error rate (QBER) of ~ 3.4%. An efficient error correction algorithm, Turbo Code, is employed. Compared with the current error correction algorithm of Cascade, a high-efficiency error correction is realized by Turbo Code with only one-time data exchange. For a low QBER, with only one-time data exchange, the final key rates based on Turbo code are similar with Cascade. As the QBER increases, Turbo Code gives higher final key rates than Cascade. Our results experimentally demonstrate the feasibility of satellite-ground QKD and show that the efficient error correction based on Turbo Code is potentially useful for the satellite-ground quantum communication.

18.
Biochim Biophys Acta ; 1852(9): 1796-804, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26071646

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease of unknown cause that typically leads to respiratory failure and death within 3-5years of diagnosis. TGF-ß1 is considered a major profibrotic factor. However, TGF-ß1 is necessary but not sufficient to the pathogenesis of fibrotic lesion of the lungs. Recent observations have revealed that calpain, a calcium dependent protease, plays a pivotal role in tissue remodeling and fibrosis. However, the mechanism of calpain mediating pulmonary fibrosis is not understood. Calpain conditional knockout (ER-Cre(+/-)capns1(flox/flox)) mice and primary human lung fibroblasts (HLFs) were used here to investigate the relationship between calpain and TGF-ß1. Calpain knockout mice were protected from fibrotic effects of bleomycin. Bleomycin induced increases in TGF-ß1 via calpain activation in HLFs. Moreover, TGF-ß1 also activated calpain. This crosstalk between calpain activation and TGF-ß1 triggered the downstream signaling pathway including TGF-ß1 Smad2/3 and non-Smad (Akt) pathways, as well as collagen-I synthesis. Taken together, our data indicate that the crosstalk between calpain activation and TGF-ß1 augments collagen-I synthesis in HLFs and in pulmonary fibrosis. Intervention in the crosstalk between calpain activation and TGF-ß1 is a novel potential strategy to prevent pulmonary fibrosis.

19.
Am J Physiol Lung Cell Mol Physiol ; 311(1): L145-53, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27261452

RESUMO

Pleural fibrosis is defined as an excessive deposition of extracellular matrix (ECM) components that results in destruction of the normal pleural tissue architecture. It can result from diverse inflammatory conditions, especially tuberculous pleurisy. Pleural mesothelial cells (PMCs) play a pivotal role in pleural fibrosis. Calpain is a family of calcium-dependent endopeptidases, which plays an important role in ECM remodeling. However, the role of calpain in pleural fibrosis remains unknown. In the present study, we found that tuberculous pleural effusion (TPE) induced calpain activation in PMCs and that inhibition of calpain prevented TPE-induced collagen-I synthesis and cell proliferation of PMCs. Moreover, our data revealed that the levels of angiotensin (ANG)-converting enzyme (ACE) were significantly higher in pleural fluid of patients with TPE than those with malignant pleural effusion, and ACE-ANG II in TPE resulted in activation of calpain and subsequent triggering of the phosphatidylinositol 3-kinase (PI3K)/Akt/NF-κB signaling pathway in PMCs. Finally, calpain activation in PMCs and collagen depositions were confirmed in pleural biopsy specimens from patients with tuberculous pleurisy. Together, these studies demonstrated that calpain is activated by renin-angiotensin system in pleural fibrosis and mediates TPE-induced collagen-I synthesis and proliferation of PMCs via the PI3K/Akt/NF-κB signaling pathway. Calpain in PMCs might be a novel target for intervention in tuberculous pleural fibrosis.


Assuntos
Calpaína/metabolismo , Tuberculose Pleural/enzimologia , Adolescente , Adulto , Idoso , Angiotensina II/fisiologia , Proliferação de Células , Células Cultivadas , Colágeno Tipo I/biossíntese , Ativação Enzimática , Epitélio/patologia , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Pleura/microbiologia , Pleura/patologia , Derrame Pleural Maligno/enzimologia , Sistema Renina-Angiotensina , Transdução de Sinais , Tuberculose Pleural/patologia , Adulto Jovem
20.
Mol Cancer ; 14: 92, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25928015

RESUMO

BACKGROUND: Irinotecan is a camptothecin analogue currently used in clinical practice to treat advanced colorectal cancer. However, acquired resistance mediated by the drug efflux pump ABCG2 is a recognized problem. We reported on a novel camptothecin analogue, FL118, which shows anticancer activity superior to irinotecan. In this study, we sought to investigate the potency of FL118 versus irinotecan or its active metabolite, SN-38, in both in vitro and in vivo models of human cancer with high ABCG2 activity. We also sought to assess the potency and ABCG2 affinity of several FL118 analogues with B-ring substitutions. METHODS: Colon and lung cancer cells with and without ABCG2 overexpression were treated with FL118 in the presence and absence of Ko143, an ABCG2-selective inhibitor, or alternatively by genetically modulating ABCG2 expression. Using two distinct in vivo human tumor animal models, we further assessed whether FL118 could extend time to progression in comparison with irinotecan. Lastly, we investigated a series of FL118 analogues with B-ring substitutions for ABCG2 sensitivity. RESULTS: Both pharmacological inhibition and genetic modulation of ABCG2 demonstrated that, in contrast to SN-38, FL118 was able to bypass ABCG2-mediated drug resistance. FL118 also extended time to progression in both in vivo models by more than 50% compared with irinotecan. Lastly, we observed that FL118 analogues with polar substitutions had higher affinity for ABCG2, suggesting that the nonpolar nature of FL118 plays a role in bypassing ABCG2-mediated resistance. CONCLUSIONS: Our results suggest that in contrast to SN-38 and topotecan, FL118 is a poor substrate for ABCG2 and can effectively overcome ABCG2-mediated drug resistance. Our findings expand the uniqueness of FL118 and support continued development of FL118 as an attractive therapeutic option for patients with drug-refractory cancers resulting from high expression of ABCG2.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Benzodioxóis/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Indolizinas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Proteínas de Neoplasias/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Animais , Benzodioxóis/química , Benzodioxóis/farmacologia , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Inativação Gênica , Humanos , Indolizinas/química , Indolizinas/farmacologia , Irinotecano , Neoplasias Pulmonares/patologia , Camundongos SCID , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores da Topoisomerase/farmacologia , Inibidores da Topoisomerase/uso terapêutico , Resultado do Tratamento
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